Speedometer.



I W ar s. A. ASQUITH. SPEEDOMETER.

APPLICATION FILED JULY 3. 1914.

1,164,908. Patented Dec. 21, 1915.

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COLUMBIA PLANOGRAPH GOUWASHINGTON; n. c.

..To all whom it may concern s s'ra FATE .STEAD A. ASQUITH, or WATERLOO, Iowa.

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' SPEEDOMETER.

Be it known that I, STEAD A. ASQIU'ITEII, a citizen of the United States of America,

.Myinvention relates to improvements in speedometers, andt-heob ect of myv improvement is to provide damping means for actingupon the driven parts .usedin the apparatus to prevent excessive oscillations there- ,ofand render its action equable and uni- .form. This object I have accomplished by the means which are hereinafter described .and: claimed, and which are illustrated ,in

the accompanying drawings, in which:

,Figure 1 1s a vertical ax1alsect1on1of the mechanism of a speedometer,-show1ng my improved damping means operatively' connected therewith, and with parts of said apparatus broken away. Fig. 2 is an upper plan view of. the parts shown in said Fig. 1, with the spiral spring removed. Fig. 3 is a detail view in partial section on a somewhat larger scale of the disk mounted on the spring-carrying spindle, and the damping spring in operative contact'with. said disk. I

Fig. 4 is a like view, showing a modified form of the latter spring, with thendisk omitted. Fig. 5 is a like view to thatof said Fig. 3, with a modified form of disk used in combination with the form of spring shown in said Fig. 4. Fig. 6 is an upper plan View of the parts shown in said Fig. 5. Fig. 7 is a detail perspective view of the cam-disk.

S1m1lar numerals of reference denote cor responding parts throughout the several views.

Referring first to Fig. 1, the numeral 15 denotes a rotary driving head carrying a plurality of spaced concentric upwardly opening cups 13. Said driving head is mounted in ball bearings, and is driven by operative connections to the carrying wheels of the vehicle. The numeral 9 denotes a rotary spindle of much smaller diameter than the driving head 15, and having its lower portion seated in jeweled step bearings 14 in the bottom of an axial hollow in the upper end ofsaid driving head. Said spindle 9 carries a plurality of spaced concentric cups 12- opening downwardly and which depend between said other cups 13 but not far enough to touch the bottom of the cups Specification of Letters Patent.

Patented Dec. 21, 1915.

Application filed Ju1y 3,1914. Seria1;No.- 848,984.

.13. The upperpart of said spindle 9 is .rotatably mounted ina jeweled bearing 11,

in a fixed support plate .6, and extends therethroughnin a diminished diameter to the bracket arm '1, which latter is fastened to the supportfiby means of thescrew 8. The numerals 4 and 5 denote upright projectionspunched upwardly from thesupporting plate. 6 at varying distances from the spindle9, and a spiral spring 10 has its outer end secured to the projection 4 while the inner end of said spring is secured tothe upper end of said spindle 9. The numeral 1 denotes a cam-disksecured on the. spindle 9 just below the spiral spring 10,- and a narrow flat spring 3 has one end in rubbing contact with the circumferential edge of said disk, the other end of said ,Spring g' b ing secured to the other upright projection 5.

ihasits free end beveled in the same direction and lies in the path of movement of the detent 2 as the disk 1 rotates.

In Figs. 4 and 6, inclusive, is shown a spring 16 and similarly mounted, whose free end is bent upon itself twice in such a manner as to provide a short offset extremity 17. In said Figs. 5 and 6 is also shown a modified form of cam-disk 19 which answers to the other cam 1 and which is also of spiral contour, but the detent thereon is prolonged spirally at 18 about a considerable arcof the circumferential edge of the cam to provide an interspace 20, into which extends the curved extremity 17 of the spring 16 to effect a rubbing contact with said cam.

The cam-disk 1 and said spring 3, also the similar cam 19 and spring 16 are used to equalize the movements of the driven cups 12, to dampen or remove the vibrations thereon caused by unusual jolts of the vehicle which would render the indicating means unsteady. Since the indicating numerals are placed on the outer periphery of the outermost cup 12 so as to be seen 1n succession answering to the other spring 3 through a window provided in the casing of the speedometer, any unusual vibrations or jars are reproduced in magnified formon the very light and easily moved cups l2 so that the dampening effect thereon produced by the rubbing of the spring 3 over theedge of the cam l is necessary to prevent such vibrations and render theindex steady at :all times. The driving-head 15 with its attached cups 18, moves the air thereabout to exert an air-pull-on the cups 12 to drive the latter against the 'tensionof the springlO,

the'speed of rotation. The spiral'form of the cam 1' causes'it to progressively increase the dampening effect as the speed ofthe vehicle increases, which is necessary, since I vibrations are more numerous and more powerfulw1th such increase of speed.

The spring 3 might drop over the camdetent because the bevel on its end causes it to engage and slide ofi the beveled Wall of the detent upon said shelf when the speed vlimit of the device is exceeded, but will fall upon the side shelf of the cam and will not lock with the detent, but the cam is free to move under it as before to the right place.

7 The modified form of disk and spring shown 1 claim as new, and desire to secure by Letters will work in the same manner, returning the cam to its right position under the rubbing sp v f Having described my lnvention, what I Patent, is:

' 1. In a speedometer, a fixed support, a

rotary shaft mounted therein, a yieldable V resilient connection between said shaft and Copies of this patent may be obtained for of June, 1914;

said support, a cam mounted on said shaft I andhaving its rubbing edge interrupted at one point abruptly from one level to another and beveled laterally, a by-passshelf along pushed by its beveled edgeupon said by-pass shelf;

' 2. In a speedometer, a support, a. rotatable winding the latter more'or less according to shafttherein, a cam having a spiral edge and mounted on said shaft with an abr'uptf'all from its point of widest to its'point of leastdiameter, 7 said cam being cut away on one side to provide a shelf therealong past said point of change-of diameters to com municate' from said place of least diameter to a place on the cam edge spaced from said -point, the projectionformed at vsaid place of, transition being beveled laterallytoward its cut away side, and a flat spring mounted on said support and having its free end seated in rubbing contact with said cam edge in the plane of the same and having its extremity beveled obliquely in the same direction asthe bevel of said projectionto e engage the latter when the cam is rotated a certain distance to be pushed thereby upon said shelf. V 'f Signed at Waterloo, Iowa,this-18th day STEAD A. ASQUITI-I. Witnesses:

G. G. KENNEDY, V I PEARL STANTON.

five cents each,';b y addressing the. Commissioner of Patents; Washington, 30.0. I i 

